KR20060052930A - Material having sound-damping and adhesive properties - Google Patents

Abstract

A damper material (3) having a loss factor tand of at least 0.25, and two glass transition temperatures of which at least one is substantially close to the use temperature of the material.

Description

MATERIAL HAVING SOUND-DAMPING AND ADHESIVE PROPERTIES

The present invention relates to a damping material for inserting between two components so that noise generated by vibrations propagating from one element to another is subjected to acoustic reduction.

This type of material is used, for example, as a sealing-type strip in vehicles, in particular in the windows of motor vehicles, to improve acoustic stability. The use of the material is described in more detail in the case of vehicle windows, but the use is not limited, and its use is limited to damping material, such as glazed walls with partitions within the building. The damping material may be for any element inserted.

Patent DE 198 06 122 describes a strip with acoustically damping material located about the periphery of the window. The strip is used primarily to secure window panes to the vehicle's bodywork, but also serves to attenuate. The strip is hollow, filled with pasty material with the ability to damp vibrations, and consists of a bonding material that becomes elastic after crosslinking.

However, the above solution has the disadvantage of not recognizing that the stiffness of the strip is sufficient to prove the desired acoustic performance. This is intended to first compress the strip, which is a coextruded bead, between the window and the body, but the compression method combined with the material of the strip does not guarantee the desired final size shape. Because it does not.

Next, the paste material inside the body of the strip remains soft and no limitations are guaranteed after the compression of the coextruded beads to the body components, which means that the body of the strip made of the binder material must be pasted before crosslinking. Because of this, it poses a risk of internal kneading material flowing over the body of the strip during deposition.

Another disadvantage is that since the damping material also has no binding, it is necessary to bind and even wrap the damping material with the binding material.

Finally, for example, the binding material may be reduced by the amount of material that can be used to secure the window to the vehicle body by bonding, or by simplicity in which the task of joining the components of the vehicle is performed. While the product gives such other functional additional properties, which may in particular include acoustic damping materials, it always lowers manufacturing costs and speeds up production in the production lines of products such as motor vehicles. On the other hand, it is desirable to provide the product with particularly attenuating properties, such as other functionalities, which may include, for example, binders.

As a result, it is an object of the present invention to provide a material having an acoustic damping material which also constitutes a binding material intended to fix the two elements to one another, if necessary, which material is between the two components in order to perform the acoustic damping role. It is inserted in.

Therefore, the present invention relates to a damping material consisting of a single component having at least one loss factor (tanδ) and two glass transition temperatures, at least one of which is at least one substantially close to the temperature of use of the material.

As is known, it should be considered that the loss factor of a material is defined as the ratio of the dissipation of the material to the strength (E ') of the material.

The expression “material composed of a single component having two glass transition temperatures” means a material composed of a plurality of components, but as described below, eventually forms one polymer having two glass transition temperatures. And material produced by physical mixing of two thermoplastic (non-reactive) polymers, each with one glass transition temperature.

According to the features. It does not exceed 2000 MPa for a frequency of 50 Hz to 500 Hz, and preferably has an intensity E 'of less than 1000 MPa at temperatures of -60 ° C and -10 ° C.

Advantageously, it has a glass transition temperature of -60 ° C to -10 ° C and a glass transition temperature of -10 ° C to + 40 ° C.

According to another feature, it has an intensity E 'of 1 MPa to 200 MPa for a frequency of 50 Hz to 500 Hz at a temperature of + 30 ° C to + 100 ° C.

Materials having the above characteristics include the following materials.

a)-based on polyether polyols, polyethylene oxide (PEO) or polyTHF type of polypropylene glycol or based on polybutadiene polyol, polycaprolactone polyol one-component polyurethanes or two-component polyurethanes based on polycaprolactonepolyol

 Polyurethanes with methoxysilane or ethoxysiloane end groups such as SPUR polymers SP XT 53 and SP XT 55 sold by Hanse Chemie;

At least one component selected from silane-modified polyether polyols (SMP) of polypropylene oxide type

b) plasticized PVC, amorphous polyester polyols, polyester polyols with methoxysilane or ethoxysilane end groups, monocomponent polyurethane prepolymers, 2 At least one component selected from component polyurethanes

Preferably the material comprises a mixture of at least two prepolymers, each based on polyether polyols and / or polyester polyols and having isocyanate end groups or methoxyl silane end groups or ethoxysilane end groups.

According to a preferred embodiment, the material having two glass transition temperatures comprises the following mixture and the NCO ratio is 0.5 to 2%.

At least one polyether polyol having a functionality of 2 including an OH number of 25 to 35 (iOH), a glass transition temperature (Tg) of less than -50 ° C and a molecular weight of 3500 to 4500;

At least one polyether polyol of 2.3-4 functionalities, including an OH number of 25-800 (iOH), a glass transition temperature (Tg) of less than -50 ° C;

At least one polyether polyol having a functionality of 2 comprising an OH number of 20 to 40 (iOH) and a glass transition temperature (Tg) of -40 ° C to -20 ° C;

At least one polyether polyol having a functionality of 2, including OH water (iOH) of 30 to 90, glass transition temperature (Tg) of 0 ° C to 30 ° C, and a softening point of 50 ° C to 70 ° C; polyether polyol)

At least one functional isocyanate of 2.1 to 2.7 having an NCO ratio of 11% to 33% of the diphenylmethane diisocyanate (MDI) type;

At least one catalyst;

Optionally a filter of molecular sieve type; And

-Optionally a chalk, kaolin, talc, alumina, carbon black or graphite type filter.

According to a first example of a preferred embodiment of the invention, the material comprises the following and the NCO ratio is 1.8-2.2%:

180-220 g of polyether polyol having a functionality of 2, including OH number of 25 to 35 (iOH), glass transition temperature (Tg) of less than -50 ° C, and molecular weight of 3500 to 4500;

75-115 g isocyanate of MDI-type with% NCO of 11.9%

5-30g carbon black

0.5-3 g of catalyst

10-30 g pyrogenic silica

135-180 g of liquid and amorphous polyester polyol A comprising a number of OH groups of 27 to 34 (iOH), a molecular weight of 3500, a functionality of 2, a glass transition temperature (Tg) of -30 ° C;

35-85 g of liquid and amorphous polyester polyol B comprising a glass transition temperature (Tg) of + 20 ° C. each having a number of 27-34 OH groups (iOH), a molecular weight of 3500 and a functionality of 2;

55-110 g MDI-type isocyanates with 11.9%% NCO;

20-80 g of molecular sieve.

According to a second example of a preferred embodiment of the present invention the material comprises:% NCO is 1.5-1.8%;

70-130 g of a polyether polyol having a functionality of 2 including a number of OH groups of 25 to 35 (iOH), a glass transition temperature (Tg) of less than -50 ° C, and a molecular weight of 3500 to 4500;

70 to 130 g of polyether polyol having a functionality of 2.3 to 4, including the number of OH groups of 25 to 800 (iOH) and a glass transition temperature (Tg) of less than -50 ° C;

80-110 g of MDI-type isocyanate with 11.9%% NCO;

5-30g carbon black

0.5-3 g of catalyst

10-30 g pyrogenic silica

Number of OH groups of 27 to 34 (iOH), molecular weight of 3500, maximum acid number equivalent to 2, 250 to 350 g of functionality including glass transition temperature (Tg) of 2 and -30 ° C. Copolyester polyols;

100-140 g of MDI-type isocyanates with 11.9%% NCO;

20-60 g of molecular sieve.

The invention also relates to the use of damping materials in at least one component of the strip. Advantageously, the strip also has acoustic attenuation properties, which is characterized by an equivalent linear stiffness of at least 25 MPa and an equivalent loss factor (tan δ _eq ) of 0.25.

It should be considered that the strength is the quantity connecting the deformation of the strip and the force applied to the strip. Stiffness is defined by the rigidity of the material constituting the strip and the geometry of the strip, the strength of which is essentially a characteristic amount of material that depends on the Young's modulus (E '). to be.

As is known, the equivalent linear intensity K * _eq is a complex number that can be written as K * _eq = K ' _eq + jK'' _eq . In the above equation, K ' _eq can be named real part, equivalent real linear sriffness, and K'' _eq is imaginary part, dissipation, It corresponds to the deflection energy force of the strip which is transformed into thermal energy in the entire strip.

Moreover, the equivalent loss factor tan δ _eq is defined by the following equation. To determine the equivalent solid linear strength (K ' _eq ), dissipation (K'' _eq ) and the equivalent loss factor (tanδ _eq ) of a strip of one or more materials, the amounts of K' _eq and K '' _eq are viscous Evaluated using an analyzer (viscoanalyzer), the equivalent loss factor (tanδ _eq ) is calculated as the ratio of K '' _eq / K ' _eq .

In one variant, the material may be used in the form of a layer possessing permanent bonding force, which is coated with a protective film on two opposite sides for bonding. For this purpose, the material is chemically modified by the reaction between the prepolymers and the terminal isocyanates of the monols.

The materials of the present invention are combined with at least one component using extrusion, encapsulation, transfer molding or injection molding techniques.

In this use, the material is intended to be inserted between two components of the glass-metal, metal-metal, glass-glass, metal-plastic, glass-plastic or plastic-plastic type.

It will also be advantageously used as a material for binding to at least one component. Therefore, it is inserted between the glass substrate and the metal component, for example, to be used to fix the substrate to the metal component, for example to secure the window to the vehicle body of the motor vehicle.

Depending on the method of manufacture, for example, the element intended to incorporate additional fastening material without interfering to some extent a batch line for producing a product incorporating a component that must have an attenuating material. Used to bind the damping material. In addition, the additional fixing material may be the damping material of the present invention.

Other advantages and features of the present invention will become apparent from the description of the accompanying drawings.

1 is a partial cross-sectional view of an element joined by means of a strip formed by the material of the present invention.

2 and 3 show, in partial cross-section, alternative embodiments of two elements joined together by a strip comprising at least the inventive material.

1 is a partial cross-sectional view of a window 1 coupled to a carrying element 2, such as an automobile body. A window made of at least one glass substrate is fixed to the vehicle body by a strip 3 formed by the material of the invention with acoustic damping and bonding properties.

As a result, the material used in the strip 3 which is coupled and inserted between two elements of the two elements 1 and 2 here, for example, the body and the window, respectively, is dust separate from the vibration damping role according to the invention. The two elements each act as a device for securing together while providing a sealing function to protect the passenger seat of the vehicle from environmental attacks such as moisture, water and water.

However, the material used for the coupling function is not directly fixed in the element that performs the attenuating role between them, but rather as a fixing element to the element or elements, which is called a fixed material in the rest of the description. It can be coupled to at least one material that runs (FIGS. 2 and 3). The material of the present invention will in any case play a role in binding to a fastening material which may also consist of the damping material and the binding material of the present invention.

The material of the present invention has two glass transition temperatures: -10 ° C to + 40 ° C ambient glass transition temperature for the material to perform the damping role, and -60 ° C to maintain the bonding function. A low glass transition temperature of -10 ° C, ie it has a temperature without the risk of failure of adhesion with the element to which the material binds.

It should be considered that the glass transition temperature corresponds to the temperature at which the loss factor tan δ is maximum.

It should be thought that the loss factor tan δ can be written as

 E 'is the strength of the material, E' 'is dissipative, that is, the deformation energy of the material that can be transformed into thermal energy in the material.

In the present invention, the damping role of the material is defined as the value that the loss factor (tan δ) of the material should be 0.25 or more.

The present invention also contributes to the durability of the bond at low temperatures when the stiffness or Young's modulus E 'of the material is 2000 MPa or less for frequencies of 50 Hz to 500 Hz.

The tan δ and E ′ measurements are measured using a viscoanalyzer, a device well known to those skilled in the art, such as experts in polymers and acoustics. Viscosity analyzers measure Young's modulus (E ') by measuring the Young's modulus (E') and dissipation (E '') and calculating the loss factor (tanδ), which is the E '' / E 'ratio. It is possible to get

For example, the viscosity analyzer is sold under the brand name METRAVIB. The measurement conditions are given below:

Sinusoidal stressing

A test piece of material constituting a rectangular parallel pipe having a size as in the range defined by the manufacturer of the viscosity analyzer:

 * Thickness e = 3 mm

 * Width L = 5 mm

 * Height = 10 mm

-Dynamic amplitude: ± 5 × 10 ^-6 for the remaining positions

Frequency range: 5 to 400 kHz

Temperature range: -60 to + 60 ° C

The material of the present invention is polyolefin, ethylene-propylene-diene (EPDM), or rubber, in particular butyl rubber, nitrile rubber or styrene-butadiene a mixture of at least one of plasticized polyvinyl chloride or unplasticized polyvinyl chloride and / or one element or two, which may or may not be deformed by an elastomer such as rubber. It will comprise a mixture of at least one of the polyurethanes of the two elements and, optionally, will include at least one catalyst.

In particular, this is a mixture of a) and b) below.

a) at least one component selected from

 -Based on polypropylene glycol, polyethylene oxide (PEO) or polyether polyols of type polyTHF, based on polybutadiene polyol, or other polycaprolactin One or two elements of polyurethanes based on polycaprolactonepolyol,

Polyurethanes with methoxysilane end groups or ethoxysilane end groups such as SPUR polymers SP XT 53 and SP XT 55 sold by Hanse Chemie, and

Silane-modified polyether polyols (SMP) of the polypropylene oxide type; And

b) at least one component selected from the following elements: polyester polyols with plasticized polyvinyl chloride, amorphous polyester polyols, methoxysilane end groups or ethoxysilane end groups , One component polyurethane prepolymer, two component polyurethane.

It should be noted that the advantage of the prepolymer with methoxysilane or ethoxysilane end groups, preferably methoxysilane end groups, is moisture-curable without foam. Polyurethane compositions can be made of elastomers, in particular nitrile, SBR or butyl rubber, thermoplastic elastomers, or else having some degree of flexibility, such as polyolefins or soft polyvinyl chloride. It may be modified by a noncrosslinkable polymer.

Of the moisture-curable and / or heat-curable one-component polyurethane prepolymer compositions, these are either polymeric or nonpolymeric diisocyanates (either aliphatic or aromatic). It is obtained by reaction between and polyol.

The polyols of the composition will comprise polyether polyols comprising the following types: fatty acid dimers, aromatic diacids or aliphatic diacids, castor oil, 1, 3- or 1,4-butanediol (butandiol), diisopropyl glycol, 2,2-dimethyl-1,3-propanediol (2,2-dimethyl-1,3-propanediol), hexanediol ( polyethylene, propylene oxide, polytetramethylene oxide, whether amorphous or crystalline, aromatic or aliphatic based on hexanediol) and carbitol type chain extenders Polycarbonate polyols or polybutadienepolyols, polyester polyols. The molecular weight of these polyols will be defined by their hydroxyl number (iOH) according to ASTM E 222-94 standard as the number of mg of potassium hydroxide equivalent to the hydroxyl content of 1 g of polyol. The hydroxyl number (iOH) used ranges from 5 to 1500. The action of such polyols will be in 2-6.

Isocyanates are aromatic in diphenylmethane diisocyanates (MDI), toluene diisocyanates (TDI), isophorone diisocyanates (IPDI), and hexane diisocyanates (HDI). Or aliphatic. The nature of the isocyanates is also defined by the NCO ratio and the ratio by weight of the current isocyanate (NCO) functionality in the product according to the ASTM D 5155-96 standard. The action of the product is 2.1 to 2.7.

The catalyst required for the reaction between the polyol and the isocyanate will be a tin catalyst such as dibutyltin dilaurate (DBTDL) and tin octoate. It is also possible to use catalysts based on morpholines such as bismuth catalysts or dimorpholinodiethyl ether (DMDEE).

The components of the above-mentioned materials are talc, silica, calcium carbonate, kaolin, alumina, molecular sieve, carbon black and graphite. (graphite), pyrogenic silica, glass microbeads, such as metal filters, zinc oxide, titanium oxide, alumina, magnetite, or micronized lead organic or mineral filters, such as micronized leads). The content of this filter will vary from 0 to 50% of the weight of the final composition.

Moreover, it would be advantageous to add an antifoam additive to interfere with the prepolymer selected from the foam, which is based on bis-oxazolidines. Eventually, also various plasticizers will be added advantageously to the prepolymer selected above.

Therefore, the material of the present invention will comprise the following preferred mixtures:

At least one polyether polyol having a functionality of 2 having a number of OH groups of 25 to 35 (iOH), a glass transition temperature (Tg) of less than -50 ° C, and a molecular weight of 3500 to 4500;

At least one polyether polyol having a functionality of 2.3 to 4 with a number of OH groups of 25 to 800 (iOH), a glass transition temperature (Tg) of less than -50 ° C;

At least one polyether polyol having a functionality of 2 having a number (iOH) of 20 to 40 OH groups, a glass transition temperature (Tg) of -40 to 20 ° C .;

At least one polyether polyol having a functionality of 2 having a number of OH groups of 30 to 90 (iOH), a glass transition temperature (Tg) of 0 to 30 ° C. and a softening point of 50 to 70 ° C .;

At least one isocyanate having a functionality of 2.1 to 2.7 having an NCO ratio with 11 to 33% of the diphenylmethane diisosyanate (MDI) type;

At least one catalyst;

Optionally, a filter of molecular sieve type; And

Optionally, a filter of chalk, kaolin, talc, alumina, carbon black or graphite

The NCO ratio of the polyurethane prepolymer is 0.5 to 2%.

Examples of the material (Example 1) according to the composition or the mixture described above are as follows.

Final mixture weighing 800 g:

218 g of functional polyether polyol 2 having a number of OH groups of 25 to 35 (iOH), a glass transition temperature (Tg) of less than -50 ° C, and a molecular weight of 3500 to 4500 (e.g. BASF Sold by Lupranol 2043 ^TM )

96 g of isocyanates of the MDI type with% NCO of 11.9%;

16 g of carbon black; And

-1.5 g of PC CAT DMDEE sold by Huntsman and sold by DMDL or Nitroil

All of the above components are mixed to form a first preblend. This reaction is carried out for 1 hour and then 16 g of pyrogenic silica (eg AEROSIL 200 ^™ sold by Degussa) is dispersed for 5 minutes.

The second premix is produced in the following way:

Amorphous polyester polyol A (polyester) having, for example, the number of 27-34 OH groups (iOH) sold by Degussa, a molecular weight of 3500 and a glass transition temperature (Tg) of 2, -30 ° C. polyol A) and 167 g of liquid;

A liquid amorphous polyester polyol B (polyester) having, for example, a number of 27 to 34 OH groups (iOH), a molecular weight of 3500 and a functionality of 2, each having a glass transition temperature (Tg) of + 20 ° C. sold by Degussa. 73 g of polyol B); And

83 g of MDI-type isocyanate with% NCO of 11.9%.

The second premix is then added to the first premix. The reaction is carried out for an additional 1 hour, 40 g of molecular sieve are dispersed for 5 minutes and the final product constituting the material of the invention is packaged in a sealed packaging step. The% NCO of the final product is between 1.8 and 2.2%.

The Young's modulus and loss factor at 120 Hz and 20 ° C for Example 1 are as follows: E '= 22 MPa, tan δ = 0.75. The Young's modulus at -40 ° C is 900 MPa.

Another embodiment (Example 2) is as follows:

For the final mixture of 800g weight:

107 g of a polyether polyol having a functionality of 2 having a number of OH groups of 25 to 35 (iOH), a glass transition temperature (Tg) of less than -50 ° C, and a molecular weight of 3500 to 4500;

-A functional 2 polyether having, for example, the number of 25-800 OH groups (iOH), Lupranol 2090 ^™ sold by BASF, a glass transition temperature (Tg) below -50 ° C, and a molecular weight of 3500-4500 107 g of polyether polyol;

96 g of isocyanates of the MDI type with% NCO of 11.9% (for example MP 130 sold by BASF);

16 g of carbon black; And

-1.5 g of PC CAT DMDEE sold by Huntsman and sold by DMDL or Nitroil

All of the above premixes are mixed to form the first premix. This reaction is carried out for 1 hour and 16 g of pyrogenic silica (eg AEROSIL 200 sold by Degussa) is dispersed for 5 minutes.

The second premix is produced in the following way:

-323 g of a copolyester polyol comprising a number of OH groups of 27 to 34 (iOH), a molecular weight of 3500, a maximum acid number equivalent to 2, a functionality of 2, and a Tg of -30 ° C; For example, a nose sold by Degussa, based on the reaction between ethylene glycol, diethylene glycol and neopentyl glycol on the one hand and the reaction between adipic acid and terephthalic acid on the other hand Polyester polyols; And

121 g of MDI-type isocyanate with 11.9%% NCO.

The second premix is then added to the first premix. The reaction is carried out for an additional 1 hour, 40 g of molecular sieve are dispersed for 5 minutes and the final product is packaged in a sealing step. The% NCO of the final product is 1.5-1.8%.

The values of Young's modulus and loss factor at 120 Hz and 20 ° C for the damping material are as follows: E '= 17 MPa, tan δ = 0.42. The Young's modulus at -40 ° C is 700 MPa.

Therefore, the present invention with two glass transition temperatures, a Young's modulus E 'of 2000 MPa or less, which is consequently a low temperature glass transition temperature of -60 ° C to -10 ° C, allows the material to be bonded at a temperature of -60 ° C to -10 ° C. It makes it possible to maintain a bond with the element.

The following table shows an example of a material composition of the invention whose Young's modulus is 2000 MPa or less at a temperature of -40 ° C (measured at a frequency of 120 Hz) and has a loss factor (tanδ) of 0.25 or more at a temperature of -10 ° C to + 40 ° C. Prove effective attenuation

It should also be noted that when the material is used as attenuating material it is necessary to take into account the loss factor (tanδ) at the temperature at which the material will be used. Therefore, if the use of the material at -40 ° C is desired, the first example material will not be suitable in the following table indicating that the loss ratio tanδ is 0.15 at -40 ° C and 0.8 at -10 ° C, but -10 It will be very sufficient at temperatures.

Two-component mixtures mixed at 40/60 weight ratio E '(MPa) at -40 ° C Tanδ at -10 ° C to + 40 ° C Tanδ at -40 ° C One-Component Polyurethane / Polyester Polyurethanes Based on Polyether Polyols 500 0.8 at -10 ℃ 0.15 Plasticized PVC with 50% diisodecyl phthalate with one-component polyurethane / 73K modulus based on polyether polyols 9 0.33 at 0 ° C 0.75 Plasticized PVC with 100% diisodecyl phthalate with one-component polyurethane / 73K modulus based on polyether polyols 15 0.42 at 0 ° C 0.65 One-component polyurethane / amorphous polyester polyols comprising silane end groups based on polyether polyols 160 0.85 at + 40 ° C 0.5 One-Component Polyurethane / One-Component Polyurethane Based on Polyester Polyols with Silane End Groups Based on Polyether Polyols 50 0.45 at + 10 ° C 0.62

Moreover, it is a material of the invention which can be a material having an intensity (E ') of 1 to 200 MPa at or above room temperature, i.e., from + 30 ° C to + 100 ° C, which avoids cohesive failure with components to which the material is bound. Will be advantageous.

 Comparative adhesion tests are consequently performed between a material according to the invention having two glass transition temperatures, including one of a lower temperature, and a material having one glass transition temperature and acoustic damping properties at ambient temperature.

The adhesion of the crosslinked material is performed on different substrates and at different temperatures by a 90 ° peel teat with a tensile tester. For further details on the nature of the test, the reader will refer to Renault recommendation D511709 / C for incorporating a mastic into a fixed car.

Strips of material 1 cm wide, 4 mm thick, and 15 cm long were applied to the substrate, which were then crosslinked for 7 days in the set air (50% relative humidity at 23 ° C.).

Tensile testing is then performed at 90 ° perpendicular to the substrate at a rate of 100 mm / min. The type of break (adhesion or cohesion) and the peel force are reported in N / linear cm. This peel force coincides with the force on the material that begins to debond at the substrate in case of adhesive failure and the force at which the material breaks in case of cohesive failure.

The numerical values given in the table below are obtained on a glass substrate in which the test piece material of the present invention and the material of the comparative example are combined. Peeling experiments were performed at -35 ° C and + 25 ° C. The Young's modulus E 'was measured at 120 Hz.

Examples 1 and 2 (Ex. 1 and Ex. 2) correspond to the materials of Examples 1 and 2 described above.

Comparative Examples 3 and 4 (Ex. 3 and 4) correspond to the damping material in the temperature range of -10 ° C to + 40 ° C with only one glass transition temperature in the range of -10 ° C to + 40 ° C.

Comparative Example 5 (Ex. 5) corresponds to a damping material that does not attenuate at a temperature of −10 ° C. to + 40 ° C., such as a polyurethane bonding mastic (Gurit Betaseal sold by Dow Automotive).

Test piece -35 ° C Peeling force (N / cm) / destruction mode (adhesive or cohesive) + 25 ° C peeling force (N / cm) / destruction mode (adhesive or cohesive) Young's modulus at -40 ℃ (MPa) Tanδ at -10 ° C to + 40 ° C glass transition temperature Tanδ at -60 ° C to -10 ° C glass transition temperature Ex.1 50 / flocculation 60 / flocculation 900 0.75 at 0 ° C 0.38 at -42 ° C Ex.2 65 / flocculation 80 / flocculation 700 0.72 at 11 ° C 0.42 at -38 ° C Ex.3 0 / adhesion 45 / flocculation 3000 1.35 at 15 ℃ Ex.4 0 / adhesion 35 / aggregation 2600 1.11 at 7 ℃ Ex.5 62 / aggregation 70 / flocculation 350 0.85 at -38 ° C

Specimens Ex.3 and Ex.4 with one glass transition temperature are very strong at low temperatures (E 'above -40 MPa at -40 ° C), even if they are damp materials with characteristic tanδ of 0.25 or more and do not pass the peel test ( Force at -35 ° C.).

Specimen Ex.5 with one glass transition temperature passed the peel test at low temperature (-35 ° C) and at room temperature (+ 35 ° C) to have a suitable strength (350 MPa), but at a room temperature of about 20 ° C It does not always attenuate (loss factor tan δ measured to be 0.2 at 20 ° C.).

However, specimens Ex.1 and Ex.2 with two glass transition temperatures and suitable strengths below 2000 MPa pass the peel test at both low (-35 ° C) and ambient (+ 25 ° C) temperatures, and are approximately -40 ° C. Attenuation at a temperature or a temperature of about 0 ° C or 10 ° C. The glass transition temperature given here is consistent with the maximum tan δ value, but this is sufficient to have a tan δ of normally 0.25 or greater for materials with acoustic damping properties at other preferred service temperatures.

In general, the strip 3 is applied between the elements 1 and 2 in the following way: A strip 3 made of the material of the present invention is an element 1 according to the application technique described below by the inventor. Is deposited). The strip is then joined to the element 1.

The second component 2 is then applied directly to either side of the strip 3 and fixed by applying pressure to the element 2. Alternatively, the strip 3 is crosslinked and then only the element 2 is applied by being fixed through an additional fixing material 4, which will also be the damping and bonding material of the present invention (FIG. 2).

It is also possible to contemplate another application such that the damping material of the present invention is fixed to each of the elements 1 and 2 facing each other by two additional damping materials 4 ( 3).

Depending on the composition of the material, the material is crosslinked in various ways, such as at room temperature, or as infrared, ultraviolet, radio frequency, microwave or induction type.

The material will be applied for at least one of the elements to be combined with other techniques: extrusion, overmolding {encapsulation}, transfer molding and injection molding.

Extrusion technology demonstrates a consistent strip appearance. The damping material according to the present invention should have a viscosity of 100 to 500 kPa at 80 ° C. which is a material that dissolves at 50 ° C.

The material therefore has green strength and exhibits sufficient thixotropy to maintain the geometry of the material after extrusion.

The size of the strip at any point in the window for acoustic performance requirements, because the technique in which the material is overmolded on one of the elements may require the width and thickness of the non-uniform strips to the entire perimeter of the elements being joined. At the same time, it can be provided in any desired form and optimized sound performance.

The viscosity of the materials used should not exceed certain limits and the binary product should be prepared quickly.

For the transfer molding process, the reader may refer to the French patent application FR 01/15039 for further details. Therefore, the material is molded and transported to one of the elements in order to maintain the benefits of molding and to reduce molding production costs. This technique combines the advantages of extrusion and overmolding because it is possible to produce several layers of material as needed. In the case of extrusion, the wet strength and minimal viscosity of the material are required in the case of one-component materials that are moisture-crossliking. If a one-component system of thermal crosslinking is used, the setting time will be faster. Even for a two-component system, the settling time is quickly corrected.

For injection molding, the element to be bonded to the material is placed in a mold with a cavity corresponding to the form of the strip desired for production, and the molding material formed by the damping material is injected into the mold in a dissolved state. .

It should be appreciated that the material of the present invention is formed in a mixture such as at least two one-component polyurethane prepolymers. The mixture is produced as described for Examples 1 and 2; In this case, the material will be applied by extrusion using one nozzle.

However, as a variant, the mixture will be produced during application, such as by extrusion; The two prepolymers extrude the materialized element immediately after mixing into the mixing head. As another variant, the mixture of polyols extrudes the urea where the material is applied immediately after reacting with the isocyanate to the mixing head of a device suitable for bicomponent polyurethane chemistry.

It is also possible to inject a pressurized gas, such as nitrogen, into a blending head or suitable mixer, such as SEVA's name under SEVAFOAM, after physical foaming.

The application of the material in the form of a strip is explained by the method of the embodiment. This material is in the form of a layer that is coated on two opposite sides to bond with a protective layer that can be removed, after being applied to the element to which the material should be applied to the layer. It will advantageously be chemically modified to add to the material. Chemical modification is carried out by reaction between the prepolymer and the terminal isocyanates of monols.

The strip of the present invention having acoustic damping properties is inserted between two elements (1) and (2), such as a glass substrate and a car body, for glass-metal bonding for the purpose of fixing the first component and the second component to each other. If so, the method of the embodiment will be described. Other applications will be envisioned to use the acoustic attenuation strips of the present invention, for example metal-metal, glass-glass, metal-plastic, u-plastic and plastic-plastic combinations. The word "plastic" refers to plastics or polys such as epoxy, polyester, polycarbonate, polymethyl methacrylate (PMMA), acrylonitrile butadiene styrene It is understood to mean a composition based on plastics such as polypropylene (PP) and reinforcing fibers such as glass fibers and wood fibers.

For metal-to-metal bonding, for example, the metal part is joined to the body of the motor vehicle. Therefore, the mechanical elements for opening doors and windows, which are generally fixed by screws, will replace the fastening by coupling into the damping strips of the present invention to dampen noise emissions inside the passenger seat of the vehicle.

In the case of glass-plastic bonding, for example, it will be involved in fixing the rear window of the vehicle.

In the case of a plastic-plastic or plastic-metal bond, for example, it is a combination of the elements that make up the tailgate of a vehicle, or by combining glass-fiber-reinforced polyurethane to the vehicle body. polyurethane) will be involved in a combination of foam-based loops.

Claims (19)

In a damping material consisting of one element, A damping material consisting of one element having a loss factor (tan δ) of at least 0.25 and two glass transition temperatures at least one substantially approaching the temperature of use of the material. The method of claim 1, wherein the damping material has a strength (E ') of not more than 2000 MPa for a frequency of 50 Hz to 500 Hz at a temperature of -60 ° C to -10 ° C, preferably 1000 MPa. Attenuated material consisting of one element, characterized in that less than. The damping material of claim 1 or 2, wherein the damping material has a glass transition temperature of -60 ° C to -10 ° C and a glass transition temperature of -10 ° C to + 40 ° C. . 4. The single element as claimed in claim 1, wherein the damping material has a rigidity E ′ of 1 to 200 MPa at a temperature of + 30 ° C. to + 100 ° C. 5. Configured damping material. The method of claim 1, wherein the damping material is a)-one-component or two-component polyurethanes based on polyether polyols, polyethylene oxide (PEO) or polyTHF types of polypropylene glycol, based on polybutadiene polyols, or based on other polycaprolactone polyols.   Polyurethanes having methoxysilane end groups or ethoxysilane end groups, and   At least one element selected from silane-modified polyether polyols of the polypropylene oxide type; And b) at least one element selected from plasticized PVC, amorphous polyester polyols, methoxysilanes or polyester polyols having ethoxysilane end groups, monocomponent polyurethane prepolymers, bicomponent polyurethanes Attenuated material consisting of one element, characterized in that it comprises. 6. The method of claim 5, wherein the damping material comprises a mixture of at least two prepolymers based on polyether polyols and / or polyester polyols, respectively, and having isocyanate end groups or methoxysilane or ethoxysilane end groups. Damping material consisting of one element, characterized in that. The mixture according to claim 6, wherein the damping material has an NCO ratio of 0.5 to 2%. At least one polyether polyol having a functionality of 2 including an OH number of 25 to 35 (iOH), a glass transition temperature (Tg) of less than -50 ° C and a molecular weight of 3500 to 4500; Polyether polyols having a functionality of 2.3 to 4, including an OH number of 25 to 800 (iOH), a glass transition temperature (Tg) of less than -50 ° C; Polyether polyols having a functionality of 2, including OH water (iOH) of 20 to 40 and glass transition temperature (Tg) of -40 ° C to -20 ° C; A polyether polyol having a functionality of 2, including OH water (iOH) of 30 to 90, glass transition temperature (Tg) of 0 ° C to 30 ° C, and a softening point of 50 ° C to 70 ° C. At least one isocyanate of the diphenylmethane diisocyanate (MDI) type and having a functionality of 2.1 to 2.7 having an NCO ratio of 11% to 33%; At least one catalyst; Optionally a filter of molecular sieve type; And -Optionally, chalk, kaolin, talc, alumina, carbon black or graphite type filters Attenuated material consisting of one element, characterized in that it comprises. The mixture according to claim 7, wherein the damping material has an NCO ratio of 1.8 to 2.2%. 180-220 g of polyether polyol having a functionality of 2, including OH number of 25 to 35 (iOH), glass transition temperature (Tg) of less than -50 ° C, and molecular weight of 3500 to 4500; 75-115 g of isocyanate of MDI-type with% NCO of 11.9% 5-30g carbon black 0.5-3 g of catalyst 10-30 g pyrogenic silica 135-180 g of liquid and amorphous polyester polyol A, including a number of 27-34 OH groups (iOH), a molecular weight of 3500, a functionality of 2, a glass transition temperature (Tg) of -30 ° C; 35-85 g of liquid and amorphous polyester polyol B comprising a number (iOH) of 27-34 OH groups, a molecular weight of 3500, a functionality of 2, a glass transition temperature (Tg) of + 20 ° C., respectively; 55-110 g MDI-type isocyanates with 11.9%% NCO; 20-80 g of molecular sieve Attenuated material consisting of one element, characterized in that it comprises. The mixture of claim 7 wherein the damping material has a% NCO of 1.5-1.8%. 70-130 g of polyether polyol having a functionality of 2 including a number of OH groups of 25 to 35 (iOH), a glass transition temperature (Tg) of less than -50 ° C, and a molecular weight of 3500 to 4500; 70 to 130 g of polyether polyol having a functionality of 2.3 to 4, including the number of OH groups of 25 to 800 (iOH) and a glass transition temperature (Tg) of less than -50 ° C; 80-110 g of MDI-type isocyanate with 11.9%% NCO; 5-30g carbon black 0.5-3 g of catalyst 10-30 g pyrogenic silica Number of OH groups of 27 to 34 (iOH), molecular weight of 3500, maximum acid number equal to 2, functionality of 2 and 250 to 350 g with a glass transition temperature (Tg) of -30 ° C; Copolyester polyols; 100-140 g of MDI-type isocyanates with 11.9%% NCO; 20-60 g of molecular sieve Attenuated material consisting of one element, characterized in that it comprises. The method of claim 1, wherein the damping material is used as at least one constituent material of the strip. Damping material consisting of one element. The strip according to claim 1, wherein the strip has an equivalent linear strength K ′ _eq of at least 25 MPa and an equivalent loss factor tan _{eq eq} of at least 0.25 at service temperature. Damping material consisting of one element. The damping material according to any one of claims 1 to 10, wherein the damping material is in the form of a layer having a permanent bond force by chemical modification of the material performed by the reaction between the terminal isocyanate and the monols of the prepolymer, Two mutually opposite surfaces for the damping material consisting of one element, characterized in that the coating with a protective film, The damping material of claim 1, wherein the damping material is intended to be coupled to at least one element using extrusion, encapsulation, transfer molding or injection molding techniques. Damping material consisting of one element. The damping material according to any one of claims 1 to 13, wherein the damping material is two elements (1, 2) of the glass-metal, metal-metal, glass-glass, metal-plastic, glass-plastic or plastic-plastic type. Characterized in that it is intended to be inserted between, Damping material consisting of one element. 15. The method of claim 14 wherein the damping material is also used as a material for binding to at least one of the elements, Damping material consisting of one element. The method of claim 13, wherein the damping material is inserted between the glass substrate and the metal element so that it can be used to secure the substrate to the metal element. Damping material consisting of one element. 15. The damping material of claim 14, wherein said damping material is used to secure a window to a vehicle body. The method of claim 13, wherein the additional fixing material binds the damping material to an element intended to be bonded. Damping material consisting of one element. The method of claim 18, wherein the additional fixing material is characterized in that the damping material of any one of claims 1 to 12, Damping material consisting of one element.

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